Sherlock series 3, episode two, The Sign of Three: Second episode provided three mysteries for the price of one

Watson is getting married, but how ill Sherlock cope as best man? (Picture: BBC)

Sherlock season three continues in The Sign of Three as Sherlock tackles his most nerve-racking assignment yet – making the best man’s speech at John and Mary’s wedding – and in so doing both prevents a murder and closes two unsolved cases.

Watson persuades Sherlock to be the best man at his wedding, where he is delighted by the appearance of his reclusive former commanding officer, Major James Sholto. However, Sholto has been targeted by wedding photographer Jonathan Small, the brother of an army rookie killed under his command.

In his speech, Sherlock eulogises John by recounting past cases. This includes two unsolved mysteries: an attempted locked room murder (The Bloody Guardsman) and an identity-stealing womaniser (The Mayfly Man). Holmes realises these formed part of Small’s preparations to stab Sholto with a blow that only becomes fatal once his belt is removed.

Sherlock and John save Sholto while Lestrade apprehends Small. Two mysteries solved, one life saved.

The Yoko factor

With Watson married, where does this leave Sherlock (Picture: BBC)

Sherlock’s best man speech is initially awkward but ultimately poignant – from his own self-description (‘the most unpleasant, rude, ignorant and all-round obnoxious arsehole that anyone could possibly have the misfortune to meet’) to his heartfelt praise for John (‘the bravest and kindest and wisest human being I have ever had the good fortune of knowing’).

Nonetheless the most touching moment is when Sherlock slips away silently at the end, realising his best friend will no longer be permanently at his side. Mary’s presence in John’s life spells an end for the duo’s partnership, just as Yoko Ono is commonly blamed for triggering the break-up of The Beatles.

The Sign of Three

Throughout the day, Sherlock observes Mary’s increased appetite, changing taste and sickness, beating John to the diagnosis that she is pregnant – the sign of a soon-to-be family of three.

The episode is tenuously connected to the Conan Doyle novel The Sign of Four, borrowing some characters and minor plot points but otherwise this is a completely different story.

Other good stuff

Wasn’t it great to see Irene Adler, even if it was only a gratuitous blink-and-you’ll-miss-it cameo? It suggests we’ll see her again, probably next series.

Did anyone else think Sherlock was playing a real-life version of children’s game ‘Guess Who?’ with all the Mayfly Man’s ladies? No? Just me?

Like cooking a Christmas roast, this episode requires patience. The central mystery takes a long time to cook and, for its opening hour, has more than a whiff of turkey about it. However, the end result is a pleasant enough filler episode – diverting, but run-of-the-mill by Sherlock’s standards – more stuffing than turkey.

But the story is unlikely to top many fans’ favourite episode lists. For me, it took too long to pull the threads together, rendering the narrative shapeless until the closing 20 minutes. Fans upset by a perceived increase in ‘soapy’ and humorous elements at the expense of plot in the opener will have more ammunition here.

What next?

It seems that the fun of the opening stories is intended to offset a dark, intense finale involving the mysterious Charles Augustus Magnussen.

Like the first two series, you feel we’re not going to finish on an upbeat, happy ending.

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